Reversible bit drill attachment



Feb. 27, 1962 M. w. PANKOW 3,023,015

REVERSIBLE BIT DRILL ATTACHMENT Filed Jan. 5, 1960 2 Sheets-Sheet 1 INVENTOR. MELV/N W PAN/(OW Feb. 27, 1962 M. w. PANKOW 3,023,015

REVERSIBLE BIT DRILL ATTACHMENT Filed Jan. 5, 1960 2 Sheets-Sheet 2 3 INVENTOR.

M54 WA/ 44 PANA/OW ilni'ted rates 3,023,015 REVERdlBLE BIT DRIILL ATIAEHMEN'I Melvin W. Pankow, 312 W. Follett St., Sandusky, Ohio Filed Jan. 5, 1%59, er. No. 625 6 Claims. (Q1. 279-14) This invention relates to a novel combination reversible screwdriver and countersink attachment for drills.

The primary object of the invention is the provision of an attachment or accessory of the kind indicated to be chucked in the chuck of such as an electric drill, which eliminates the inconvenience, loss of time, and danger of loss or misplacement of a separate screwdriver and 21 separate countersink, and their individual chucking and unchucking in a drill chuck, for screwdriving and countersinking operations.

Another object of the invention is to provide a simple and efiicient device of the character indicated above wherein the screwdriver and countersink bits are combined in a single dual member which is reversible in a holder having a tang to be chucked in a drill chuck, and a combined hand guide and locking sleeve surrounds the holder and is movable therealong, in opposite directions, for applying and releasing means for locking the said member in the holder, the sleeve being freely rotatable on the holder so as to be capable of being held stationary, while the holder is rotated by a drill, for guiding the member relative to the work.

Other important objects and advantageous features of the invention will be apparent from the following description and the accompanying drawings, wherein, for purposes of illustration only, a specific form of the invention is set forth in detail.

In the drawings:

FIGURE 1 is a perspective view of a device of the invention chucked in the chuck of an electric drill, with the screwdriver bit disposed for use;

FIGURE 2 is an enlarged side elevation of the device per se, the sleeve being in longitudinal section;

FIGURE 3 is a longitudinal section taken on the line 3-3 of FIGURE 2, showing the sleeve in its release position;

FIGURE 4 is a view similar to FIGURE 3, showing the sleeve in locking position;

FIGURE 5 is a perspective view of the dual bit member per se;

FIGURE 6 is an enlarged longitudinal section taken on the line 66 of FIGURE 5; and

FEGURES 7 and 8 are transverse sections taken on the lines 77 and 8-8, respectively, of FIGURE 4.

Referring in detail to the drawings, wherein like numerals designate like parts throughout the several views, the numeral ltl generally designates an electric drill having a chuck 12, into which is chucked a device of the present invention, generally designated 14.

The device 14 comprises an elongated tubular holder 16, having an open first or forward end 18, a closed second or rear end 26, and a uniformly cylindrical side wall 22. A drill chuck engaging tang 24 is centered on the closed rear end 29.

The holder side wall 22 is formed, at diametrically opposed points and near to and spaced from the open forward end 13, with circular detent openings 26, whose edges include squared or normal forward portions 28 and rearwardly and outwardly angled rear portions 30; The openings 26 are not substantially larger in diameter, at their outward ends 32, than detent balls 3% which are maintained in the openings 26. The openings having in ward ends 36 which are smaller in diameter than the detent balls 34 for holding the balls against escape from the openings 26 into the interior of the holder 16, while pro 3,h23,hl5 Patented Feb. 27, l9d2 ice viding for sufficient projection of the balls into the interior of the holder for locking a dual bit member 38 in the holder.

Slidably and rotatably circumposed on the holder 16 is a combined locking sleeve and manual guide sleeve 4t which comprises a cylindrical side wall 42, which is larger in diameter than the holder, and an internal bearing annulus 44 on the forward end of the sleeve 40 which has an axial opening 4d which snugly and slidably and rotatably receives the holder 16. As shown in FIGURES 3 and 4, the holder 16 has external forward and rear annular shoulders 48 and 5t thereon, the forward shoulder 48 being a stop shoulder which is located immediately behind the detent ball openings 26. The rear shoulder Si is located substantially midway between the stop shoulder 48 and the rear end 2% of the holder 16, and is a rounded detent shoulder.

For maintaining the sleeve 46 in its forward locking position and in its rear release position, outwardly and longitudinally bowed leaf springs 52 are compressed between the sleeve side wall 42 and the exterior of the holder 16 in diametrically opposed locations. Suitable means, such as rivets 5d fix the springs 52, at midlength points thereof, to the interior of the sleeve side Wall 42, at points near to the open rear end 56 of the sleeve, so that the springs 52 have forward arms 58 extending forwardly in the space between the holder 16 and the sleeve 49, and rear arms 6%) which reach rearwardly beyond the rear end 56 of the sleeve.

The springs 52 are shorter than the distance between the shoulders 48 and 56, and their forward arms 58 ter minate in free forward ends 62 which bear Slidably and frictionally against the interior of the holder 16, and which, in the forward release position of the sleeve 40, make stop engagements with the forward shoulder 48. The rear spring arms 60 have at their rear ends, laterally inward extending detent noses 64 which have rounded tips 66, which bear frictionally and slidably against the exterior of the holder 16, flat forward sides 68 to have stop engagement behind the detent shoulder 50, and angled rear cam sides 7% for cam engagement with the rounded forward side '72 of the detent shoulder 50.

As the sleeve 40 is moved rearwardly along the holder 16, from its forward release position, shown in FIGURE 3, toward its rear locking position, shown in FIGURE 4, a concave annular cam surface 74, on the rear side of the bearing annulus 44, engages the detent balls 34 and cams them into the openings 26, at the same time that the detent noses 64- start to ride rearwardly over the detent shoulder 50. As the sleeve 40 is moved further rearwardly, the inner surface 4% of the bearing annulus 44 engages the balls 34 and forces them inwardly into the smaller inward ends 36 of the openings 26, and the noses 64 span over the detent shoulder 50 and engage retainably therebehind. The combined friction exerted by the engagement of the noses 64 and the forward ends 62 of the springs 52 with the exterior of the holder 16, serves to hold the sleeve 40 in its locking position, wherein the bearing annulus 44 holds the detent balls 34 in their inward operative positions, for retaining non-rotatably in the holder 16, the dual bit member 38.

The dual bit member 38 comprises an elongated tubular cylindrical dual socket 76 which is substantially shorter than the holder 16, and which has an axial bitreceiving bore 78 extending therethrough. The socket 76, as shown in FIGURES 5 and 6, has similar squared and bevelled first and second ends 8i and 82, respectively, and a smooth cylindrical outer surface 84, which is uninterrupted, except for an annular lateral stop flange 86 which is midway of the ends of the socket 76.

At locations close to and spaced from the socket ends 80 and 82, the outer surface 84 is indented by circumferentially extending first and second pairs of diametrically opposed recesses 88 and 99, respectively. The recesses 88 and 90 are concave and are sufficiently wide to receive the detent balls 34 and are substantially longer than the openings 26 in the side wall 22 of the holder 16, with which the recesses are severally registered when the socket 76 is operatively engaged in the holder 16, with its stop flange 86 engaged with the forward end 18 of the holder.

Removably engaged in the first and second ends of the socket bore '78 are the round shanks 92 of a screwdriver bit 94- and a countersink bit 96, the bits having, intermediate their ends, lateral stop flanges 98, to bear against related ends of the socket '76. The bit shanks 92 are held in the socket bore 78 and maintained against rotation therein by suitable means, such as dual set screws 100, threaded in radial bores 102 in the socket '76 and entering the socket bore 8-9, and engaged at their inward ends with flats 104 on the sides of the shanks 92. The bits 94 and 95 are interchangeable in the socket ends and can be bits of a set of interchangeable bits of different sizes and forms.

The dual bit member 38 is operatively engaged in the holder, with the sleeve all in its forward release position, simply by inserting the member 38 endwise through the open forward end 18 of the holder 16, until its stop flange 86 abuts the end 18, with the related one of the pairs of recesses 88 and 99 in registry with the detent balls 34 and their openings 26, and then moving the locking sleeve 40 rearwardly to its locking position, whereby the detent balls 34 are forcibly engaged in and maintained in the socket recesses. Reversing this procedure frees the socket 76 for removal from the holder 16.

It will be seen from the foregoing that the described device does away with the need for the provision of separate screwdriver and countersink bits and their individual chucking and unchucking in an electric or other drill chuck, as well as the hazard of loss or misplacement of such separate bits and the misadventures of hurriedly selecting inappropriate bits, and assures not only association together of properly related screwdriver and countersink bits, but their individual availability simply by reversing the dual bit member in the holder of the device.

Although there has been shown and described herein a preferred form of the invention, it is to be understood that the invention is not necessarily confined thereto, andthat any change or changes in the structure of and in the relative arrangements of components thereof are contemplated as being within the scope of the invention as defined by the claims appended hereto.

What is claimed is:

1. A reversible bit attachment for a drill, comprising a tubular holder having an open forward end and a rear end, drill chuck engaging means on the rear end of the holder, a dual bit member comprising a dual socket having first and second ends which are optionally engageable in the open end of the holder, an annular stop shoulder intermediate the ends of the socket engageable with the forward end of the holder, and releasable detent means having cooperating components on opposite sides of the holder and on opposite sides of the dual socket, and a sleeve slidably circurnposed on the holder and operatively engageable with components of the detent means.

2. A reversible bit attachment for a drill, comprising a tubular holder having an open forward end and a rear end, drill chuck engaging means on the rear end of the holder, a dual bit member comprising a dual socket having first and second ends which are optionally engageable in the open end of the holder, an annular stop shoulder intermediate the ends of the socket engageable with the forward end of the holder, and releasable detent means having cooperating components on opposite sides of the holder and on opposite sides of the dual socket, said detent means comprising circumferential recesses in the dual socket, said holder having a side wall formed with opposed detent ball openings with which said recesses are registrable, detent balls in said openings to project into the recesses, and sleeve means mounted on and movable along the holder for operating the detent balls into and out of engagement with the recesses.

3. A reversible bit attachment for a drill, comprising a tubular holder having an open forward end and a rear end, drill chuck engaging means on the rear end of the holder, a. dual bit member comprising a dual socket having first and second ends which are optionally engageable in the open end of the holder, an annular stop shoulder intermediate the ends of the socket engageable with the forward end of the holder, and releasable detent means having cooperating components on opposite sides of the-holder and on opposite sides of the dual socket, said detent means comprising circumferential recesses in the dual socket, said holder having a side wall formed with opposed detent ball openings with which said recesses are registrable, detent balls in said openings to project into the recesses, and sleeve means mounted on and movable along the holder for operating the detent balls into and out of engagement with the recesses, said operating means comprising a sleeve slidably circumposed on the holder, said sleeve having an internal annular cam movable across and in contact with the detent balls for moving the balls into the recesses.

4. A reversible bit attachment for a drill, comprising a tubular holder having a side wall, an open forward end, and a rear end, axial drill chuck engaging means on said rear end, a sleeve surrounding said holder and having a sidewall concentrically spaced from the holder, said sleeve having an open rear end and avforward end, an internal annulus in the sleeve at its forward end having an inner surface slidably engaged on the holder, said internal annulus having a rear cam surface, the holder side wall having opposed openings therethrough, detent balls loosely engaged in said openings, means preventing escape of the detent balls into the interior of the holder while enabling the balls to project partially into the in terior of the holder, said sleeve being rearwardly movable along the holder so as to apply said cam surface against and force the detent balls inwardly in said openings, position retaining means on the sleeve engaging the holder, said retaining means comprising an external annular stop shoulder located on the holder immediately behind the detent ball openings and an annular detent shoulder n the holder spaced between the stop shoulder and the rear end of the holder, and longitudinally and outwardly bowed leaf springs having intermediate portions secured to the interior of the sleeve side wall at the rear end of the sleeve, said springs being compressed betweenthe sleeve side wall and the outer surface of the holder and having forward arms and rear arms, said forward arms having terminal ends frictionally engaged with the outer surface of the holder and engageable with said external stop shoulder in the forward release position of the sleeve, the rearward spring arms having laterally inwardly extending cam noses frictionally engaged with the outer surface of the holder to engage retainably behind the detent shoulder in the locking position of the sleeve, said noses being adapted to ride over the detent shoulder in the transit of the sleeve to its rearward locking position.

5. A reversible bit attachment for a drill, comprising a tubular holder having a side wall, an open forward end, and a rear end, axial drill chuck engaging means on said rear end, a sleeve surrounding said holder and having a side wall concentrically spaced from the holder, said sleeve having an open rear end and a forward end, an internal annulus in the sleeve having an inner surface slidably engaged on the holder, said annulus having arear cam surface, the holder side wall having opa posed openings therethrough, detent balls loosely engaged in said openings, means preventing escape of the detent balls into the interior of the holder while enabling the balls to project partially into the interior of the holder, said sleeve being rearwardly movable along the holder from a forward release position toward a rear locking position so as to apply said cam surface against and force the detent balls inwardly in their openings, and position retaining means on the sleeve engaging the holder, an elongated dual socket having first and second ends optionally insertable in the open forward end of the holder, a lateral stop flange on the socket intermediate its ends for engagement with the forward end of the holder, different bits securably engaged in the ends of the socket, said socket having circumferential detent ball receiving recesses located adjacent its opposite ends for selective registry with detent ball openings of the holder, the detent balls being adapted to be projected into the socket detent recesses as the sleeve is moved rearwardly from its forward release position to its locking position.

6. A reversible bit attachment for a drill, comprising a tubular holder having a side wall, an open forward end, and a rear end, axial drill chuck engaging means on said rear end, a sleeve surrounding said holder and having a side wall concentrically spaced from the holder, said sleeve having an open rear end and a forward end, an internal annulus in the sleeve having an inner surface slidably engaged on the holder, said annulus having a rear cam surface, the holder side wall having opposed 30 2,959,943

openings therethrough, detent balls loosely engaged in said openings, means preventing escape of the detent balls into the interior of the holder while enabling the balls to project partially into the inerior of the holder, said sleeve being rearwardly movable along the holder from a forward release position toward a rear locking position so as to apply said cam surface against and force the detent balls inwardly in their openings, and position retaining means on the sleeve engaging the holder, an elongated dual socket having first and second ends op tionally insertable in the open forward end of the holder, a lateral stop flange on the socket intermediate its ends for engagement with the forward end of the holder, different bits securably engaged in the ends of the socket, said socket having circumferential detent ball receiving recesses, located adjacent its opposite ends for selective registry with detent ball openings of the holder, the detent balls being adapted to be projected into the socket detent recesses as the sleeve is moved rearwardly from its forward release position to its locking position, said sleeve being freely rotatable on the holder to serve as manual means for guiding a bit relative to work.

References Cited in the file of this patent UNlTED STATES PATENTS 336,762 Smith Feb. 23, 1886 1,805,005 Phillips May 12, 1931 2,658,766 Rock Nov. 10, 1953 Allen Nov. 15, 1960 

